The issue is that the extractor needs to be "clocked". The simplest is a Sako or better, M-16, style extractor. That is a pretty common change. Many aftermarket 700 clone actions have those anyway. Christensen is an example.
I have a theory, untested, that the factory 700 actions chambered in .300 AAC Blackout might come pre-clocked since the .300 BO is based on the fireball case. Haven't had a chance to look into it. If the theory is right then you should be able to just rebarrel one.
It is not a big deal, nor particularly expensive, to have a 'smith convert your rifle to the M-16 extractor. I guess that is actually superior to the Sako thing we more often hear about. I wouldn't let the extractor / needing to do that work slow me down in the slightest, just pay the money to get things set up the way you want.
The bigger issue for me has been magazine feeding. My 2 700 Fireball rifles, one an LVSF in .221, the other a 700 SPS in .17 FB, both liked to occasionally erupt spitting the whole magazine full of cartridges through the open action top and onto the ground. I replaced sheet metal, didn't seem to help. That was quite a few years ago. Could be that with all the interested in the .300 BO that new solutions exist.
Another option is a single shot action. I'd love to find a worn out XP-100 to convert to a single shot rifle. Or a Contender or Encore barrel if you happen to be into those. And of course any Ruger #1 or #3 can be as easily rebarreled to .221 or .17 FB as to anything else on that case head.
